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Peripheral veno-artertial extracorporeal membrane oxygenation (VA-ECMO) is commonly used in the paediatric population for intractable respiratory and cardiac failure. One of the devastating complications of VA-ECMO is severe brain damage due to ischemia or haemorrhage. We describe a case of peripheral cervical VA-ECMO complicated by evolving right cerebral ischemia which was rescued with rapid conversion from peripheral to central VA-ECMO support. Notably, the patient had a complete circle of Willis. Following conversion, we observed complete resolution of neurological symptoms with full functional recovery. [ABSTRACT FROM AUTHOR]

Purpose Cardiopulmonary bypass induces an ischaemia-reperfusion injury and systemic inflammatory response, which contributes to low cardiac output syndrome following cardiac surgery. Exogenous nitric oxide during cardiopulmonary bypass has shown potential to ameliorate such injury. We undertook a large randomised controlled trial to investigate the clinical effects of administering nitric oxide to the cardiopulmonary bypass circuit in children. Methods After written informed consent, children were randomised to receive 20 ppm nitric oxide to the gas inflow of the cardiopulmonary bypass oxygenator, or standard conduct of bypass. Results 101 children received nitric oxide and developed low cardiac output syndrome less frequently (15 vs. 31 %, p = 0.007) than the 97 children who did not receive nitric oxide. This effect was most marked in children aged less than 6 weeks of age (20 vs. 52 %, p = 0.012) and in those aged 6 weeks to 2 years (6 vs. 24 %, p = 0.026), who also had significantly reduced ICU length of stay (43 vs. 84 h, p = 0.031). Low cardiac output syndrome was less frequent following more complex surgeries if nitric oxide was administered (17 vs. 48 %, p = 0.018). ECMO was used less often in the nitric oxide group (1 vs. 8 %, p = 0.014). Conclusions Delivery of nitric oxide to the oxygenator gas flow during paediatric cardiopulmonary bypass reduced the incidence of low cardiac output syndrome by varying degrees, according to age group and surgery complexity. Clinical Trial Registration: ACTRN12615001376538., Author(s): Christopher James [sup.1] [sup.2], Johnny Millar [sup.1] [sup.2], Stephen Horton [sup.2] [sup.3], Christian Brizard [sup.4], Charlotte Molesworth [sup.2], Warwick Butt [sup.1] [sup.2] [sup.5] Author Affiliations: (1) grid.416107.5, 0000000406140346, Department [...]

A refined model of fault structure in the active New Madrid Seismic Zone (NMSZ) is presented based on relocated hypocenters and application of a statistical clustering method to determine fault planes. Over 200 earthquakes are recorded in the NMSZ every year, but the three‐dimensional (3‐D) fault structure is difficult to determine because the zone is covered by thick, Mississippi Embayment sediment. The distribution of earthquakes in the NMSZ indicates four major arms of seismicity, suggesting the presence of a northeast‐southwest trending strike‐slip fault system with a major northwest trending, contractional stepover fault. Relocation of 4,131 earthquakes using HypoDD resulted in major improvement in the depiction of fault structure in the NMSZ including three‐dimensional structural variations along the along the Reelfoot fault (RF) and a well‐defined intersection of the Axial and RFs. Optimal Anisotropic Dynamic Clustering analysis of the relocated hypocenters produced a fault model consisting of 12, well resolved planes. The RF is continuous along strike from the northern end to the Ridgely fault, located south of the intersection with the Axial fault (AF). The crosscutting Ridgely fault may serve as a barrier to rupture propagation along the entire fault. The strike‐slip arms of seismicity are well resolved and correspond to near vertical planes. Three planes are resolved in the southern part of the AF and are associated with the Osceola igneous complex. Plain Language Summary: A refined fault model is determined for the active New Madrid seismic zone using earthquakes that occurred from 2000 to 2019. The seismic zone is located in the central United States and poses a hazard to critical infrastructure and numerous population centers. The major faults are the Reelfoot thrust fault and the strike‐slip Axial fault (AF). The first step in constructing the improved fault model involved relocation of the earthquakes to decrease location error. The second step involved fitting planes to the relocated earthquakes under the assumption that the earthquakes cluster along fault segments. The resulting model provides a three‐dimensional representation of the fault structure. A major fault disrupts the southern portion of the Reelfoot fault, making it discontinuous. The northern part of the AF is very well defined. Earthquakes are more scattered along the southern part of the AF, but three fault planes are resolved that are located along the side of a major intrusion. The fault model can be used in studies involving possible rupture length and magnitude of large earthquakes. Key Points: New Madrid Seismic Zone hypocenters for the years 2000–2019 are relocated and have a median relative location error of 65 mPlanes are fit to the relocated hypocenters producing a detailed three‐dimensional model of fault structureThe Reelfoot fault is segmented by the Ridgely fault [ABSTRACT FROM AUTHOR]

Importance: In children undergoing heart surgery, nitric oxide administered into the gas flow of the cardiopulmonary bypass oxygenator may reduce postoperative low cardiac output syndrome, leading to improved recovery and shorter duration of respiratory support. It remains uncertain whether nitric oxide administered into the cardiopulmonary bypass oxygenator improves ventilator-free days (days alive and free from mechanical ventilation).Objective: To determine the effect of nitric oxide applied into the cardiopulmonary bypass oxygenator vs standard care on ventilator-free days in children undergoing surgery for congenital heart disease.Design, Setting, and Participants: Double-blind, multicenter, randomized clinical trial in 6 pediatric cardiac surgical centers in Australia, New Zealand, and the Netherlands. A total of 1371 children younger than 2 years undergoing congenital heart surgery were randomized between July 2017 and April 2021, with 28-day follow-up of the last participant completed on May 24, 2021.Interventions: Patients were assigned to receive nitric oxide at 20 ppm delivered into the cardiopulmonary bypass oxygenator (n = 679) or standard care cardiopulmonary bypass without nitric oxide (n = 685).Main Outcomes and Measures: The primary end point was the number of ventilator-free days from commencement of bypass until day 28. There were 4 secondary end points including a composite of low cardiac output syndrome, extracorporeal life support, or death; length of stay in the intensive care unit; length of stay in the hospital; and postoperative troponin levels.Results: Among 1371 patients who were randomized (mean [SD] age, 21.2 [23.5] weeks; 587 girls [42.8%]), 1364 (99.5%) completed the trial. The number of ventilator-free days did not differ significantly between the nitric oxide and standard care groups, with a median of 26.6 days (IQR, 24.4 to 27.4) vs 26.4 days (IQR, 24.0 to 27.2), respectively, for an absolute difference of -0.01 days (95% CI, -0.25 to 0.22; P = .92). A total of 22.5% of the nitric oxide group and 20.9% of the standard care group developed low cardiac output syndrome within 48 hours, needed extracorporeal support within 48 hours, or died by day 28, for an adjusted odds ratio of 1.12 (95% CI, 0.85 to 1.47). Other secondary outcomes were not significantly different between the groups.Conclusions and Relevance: In children younger than 2 years undergoing cardiopulmonary bypass surgery for congenital heart disease, the use of nitric oxide via cardiopulmonary bypass did not significantly affect the number of ventilator-free days. These findings do not support the use of nitric oxide delivered into the cardiopulmonary bypass oxygenator during heart surgery.Trial Registration: anzctr.org.au Identifier: ACTRN12617000821392. [ABSTRACT FROM AUTHOR]

The materialisation of space-time is a central project for capitalism. Within the finance sector, the relationship between the (exchange) value of money now and the (capital) value of money in [...]

The Gambler conjures a world of myth: not as a fiction of human consciousness but as unconscious image-language. Its ambition is to write geography as material subject. In tracing the discourse written in the built environment the text ranges over the analyses of Marx and Freud and into the gestural worlds of Kafka and the blood sports of the ancient Colosseum. It discovers the myth of New Zealand horse racing, written in pictures in the local pub where virtual racing, abstracted from the living world, (dis)plays on the television screen. Here, finally, The Gambler comes to terms with loss. Key words: cultural geography, dialectics, gambling, historical materialism, New Zealand.

The election of Sukhinder Turner as Dunedin, New Zealand's first female, first Green, and first Sikh mayor may be a reflection of the city's struggle for fairness. Imbalanced economic growth patterns may have contributed to the community's frustration. However, the re-election of all the sitting city council members appears to contradict this symbolic effort. Political, social, and economic struggles will likely continue in this community in flux.

The stratigraphy and sedimentology of Jurassic to Tertiary sediments within the Laura and Carpentaria basins in northeastern Australia show that the continental drainage divide here predates the onset of continental margin formation and has remained stationary since the Middle Jurassic. This result is contrary to models of the evolution of highlands adjacent to passive continental margins that state that divide migration associated with downwarping of the highland flank and widespread stream reversals and/or captures should occur following margin development. The results also show that a maximum of only 50 m of denudation could have occurred on the continental drainage divide here since the Cretaceous. Keywords: passive margin, tectonics, continental drainage divide, denudation.

We develop an automated strategy for discriminating deep microseismic events from shallow ones on the basis of thewaveforms recorded on a limited number of surface receivers. Machinelearning techniques are employed to explore the relationship between event hypocentres and seismic features of the recorded signals in time, frequency and time-frequency domains. We applied the technique to 440 microearthquakes-1.7

Objective: The aim of this review is to highlight an emerging problem with anticoagulation-related complications in neonatal and paediatric ECMO, to explore for flaws in the currently recommended anticoagulation management responsible for these problems and to discuss possible strategies mitigating further escalation of the issue. Data Sources: Pertinent neonatal and paediatric literature on the topic of interest and international Extracorporeal Life Support Organisation (ELSO) registry data request. Conclusions: The international ELSO registry data reveals increasing rates of anticoagulation-related complications during neonatal and paediatric ECMO worldwide. The causes are multifactorial and the proposed solution to the problem is to match anticoagulation management to the pathophysiological complexity of haemostasis on ECMO. [ABSTRACT FROM AUTHOR]

Background One potential approach for advancing univentricular heart surgical palliation outcomes is by stem cell therapy to augment right ventricular function and muscle mass. Whether the stem cell–inclusive cord blood mononuclear cells (CBMNCs) are safe to perfuse into the coronary vasculature during neonatal cardiopulmonary bypass (CPB) is unknown. We evaluated the acute safety, functional effects, and fate of human CBMNCs in a novel model of coronary vasculature delivery in a lamb model of infant CPB. Methods Neonatal lambs were randomized in blinded fashion to receive control (n = 5) or human CD45 + CBMNCs (8 × 10 6 cells/kg body weight, n = 7) treatments during CPB. Aortic cross-clamp time was 40 minutes, with maintenance blood cardioplegia delivered every 10 minutes. Pressure-volume indices were used to measure left ventricular function before CPB and 60 minutes after CPB. CBMNCs were assessed by flow cytometry and immunohistochemistry. Results CBMNC-treated lambs were hemodynamically stable after CPB, with a decline in left ventricular pressure-volume indices similar to controls. The coronary vasculature was patent on microscopy, without evidence of cell aggregates or clots. Human CD45 + cells were distributed in high abundance within all cardiac regions, predominantly the right atrium and ventricles, and trafficked beyond endothelial cell layers and between myocytes. CD45 + cells localized at low incidence in the spleen, liver, lungs, and kidneys, but rarely remained in the circulation (<0.1% of infused cells). Conclusions Coronary delivery of human CBMNCs during blood-cardioplegic arrest in a lamb model of CPB results in highly abundant myocardial distribution of cells without acute adverse effects on vascular patency and post-CPB cardiac function. [ABSTRACT FROM AUTHOR]

The horizontal-to-vertical (H/V) technique by Nakamura (1989) was applied to data from 30 new field stations and 64 other broadband temporary and permanent seismic stations within the Mississippi Embayment of the central United States to develop a 3D model of unconsolidated sediment shear-wave velocity structure. Using the Dart (1992) map of sediment thickness as a basis, two selfconsistent models of average shear-wave velocity versus sediment thickness were developed by utilizing the theoretical linear relationship between the frequency of the H/V peak and shear-wave velocity. One model was based on the observation that the H/V peak period Tp (s) versus sediment thickness h (m) was seen to be approximately linear with the relationship T p = 0.003266h + 1.084. The second model was developed by considering peak frequency f p versus sediment thickness parameterized to follow In /p = 8.325 × 10-7h² - 0.00232h - 0.01796. Overall, the models show low-average shear-wave velocity near the edge of the Mississippi Embayment with velocities increasing with increasing sediment thickness, consistent with increased sediment compaction. These models will be useful in studies of site resonance and amplification for earthquake-shaking hazards and for wave propagation computations for the region. [ABSTRACT FROM AUTHOR]

Background: Outcomes after operations for bicuspid aortic valve disease in pediatric patients were determined. Methods: Between 1977 and 2011, 146 consecutive patients underwent surgical repair of bicuspid aortic valve. Median age at operation was 207 days (range, 5 days to 16 years). Indication for surgery was stenosis in 113, insufficiency in 25, and both in 8. Valve debridement was done in 76 patients, and complex repairs in 70, including 61 who required addition of pericardial patches, consisting of the creation of a neocommissure in 55, cusp extension in 33, and a perforation repair in 6. The valve was made tricuspid in 38 patients (29 cusp extensions). Results: Twenty-year survival was 88% (95% confidence interval, 73% to 95%). After a mean follow-up of 8 ± 7 years, 35 patients needed a reintervention. Freedom from reintervention at 18 years was 43% (95% confidence interval, 28% to 56%). At the latest follow-up, an additional 13 patients without reoperation had moderate or severe stenosis, and 17 had moderate regurgitation. Seventy-eight patients had an event-free long-term outcome (no reintervention, stenosis, or regurgitation). The only independent predictive factors of an event-free outcome were not having addition of patch material at repair (hazard ratio, 12; p = 0.05) and shorter bypass time (HR, 1.01; p = 0.023). The 10-year freedom from any significant event was 60% (95% confidence interval, 46% to 71%) for those without use of patch material, whereas nearly all those with a patch repair had an adverse event at that time. Conclusions: Outcomes after surgical repair of bicuspid aortic valves in the pediatric population are excellent, especially if the repair can be performed without the addition of patches. Primary repair should be offered because long-lasting results can be achieved if the disease can be relieved by simple procedures. [Copyright &y& Elsevier]

Ambient ground-motion data were collected using phased seismic arrays in fall 2002 and spring 2007 within the Mississippi embayment and at a single station external to the embayment. These data allowed us to determine the wave-field composition of ambient noise for understanding wave-propagation mechanisms giving rise to spectral peaks using Nakamura's HIV technique. Ambient ground motions in the frequency band of 0.1-0.33 Hz (10-3 sec period) were dominated by spatially localized Rayleigh- and Love-wave microseisms generated by high-ocean waves along the North American seaboard in the time periods of analysis. Seismic waves important in forming the H/V peak near 4 sec period are composed of relatively high-phase velocity Rayleigh and Love waves that convert to propagating homogeneous shear waves in the thick unconsolidated sediments of the embayment. The H/V resonant period is controlled by both constructive and destructive interference of these shear waves. A simple relationship for the H/V peak is given using a propagator matrix formulation that predicts the resonance frequency of a layered medium for surface wave motion at the base of the system. The amplitude of the observed H/V peak, however, does not give an accurate estimate of shear-wave amplification because it depends on the slowness of the incident wave. The inconsistency in estimated average shear-wave velocities using the H/V method and differential travel times of local earthquake Sp phases in the Mississippi embayment may be explained by misidentification of Sp-wave conversion points from deeper interfaces. [ABSTRACT FROM AUTHOR]

A 13-year-old girl presented to the emergency department with fatigue, headaches and muscle stiffness after returning from a family camping trip. Within 24 h, she was transferred to ICU with general oedema and low saturations, where she had a cardio-respiratory arrest and was placed on veno-arterial extracorporeal membrane oxygenation (ECMO). The patient was successfully supported with ECMO for profound myocardial dysfunction and haemofiltration for rhabdomyolysis and acute renal failure. Patients who present with profound myocardial dysfunction and myoglobinuria as a consequence of viral infection can be successfully supported with ECMO. [ABSTRACT FROM AUTHOR]

Increasing perioperative haemoglobin level by reducing priming volume and maintaining a safe cardiopulmonary bypass (CPB) system is the aim of every perfusionist. In this study, we have compared the two membrane oxygenators and pump systems used for paediatric bypass at the Royal Children's Hospital on a regular basis since 1988. We looked at all patients who had the Cobe VPCML (Cobe Laboratories, Denver, CO, USA) and Terumo RX-05 (Terumo Corporation, Tokyo, Japan) oxygenators used for flows from 800 mL/min up to the maximum rated flow for the respective oxygenator from January 2002 until March 2004. The VPCML refers to using only the 0.4-m2 section of the oxygenator. The pump systems used were the Stöckert CAPS (Stöckert Instrumente GmbH, Munich, Germany) and Jostra HL 30 (Jostra AB, Lund, Sweden). Changing from the VPCML to the RX-05 resulted in a 37% reduction in priming volume. The introduction of the Jostra HL 30 with a custom-designed mast system reduced the priming volume by another 15%. This change in priming volume allowed a significant increase, from 6 to 34%, in the percentage of patients who received bloodless primes, and for those patients who received blood primes, an increase in haemoglobin (Hb) on bypass from 8.2 to 9.6 g/dL, on average. [ABSTRACT FROM AUTHOR]

Centrifugal pump left ventricular assist device is a useful adjunct in pediatric cardiac surgery, as a bridge to recovery, or in some cases, to transplantation. This form of circulatory support may not have the universal applicability of extracorporeal membrane oxygenation, but it is equally or more effective in properly selected patients. The technology for centrifugal pump support is now quite standardized, and the advantages well documented. In this chapter we discuss the problems of indications, case selection, technical aspects of the circuit, and general clinical management. Results since 1989 are also presented. [Copyright &y& Elsevier]

This article describes an unusually well-behaved, unusually well-documented central and eastern United States (CEUS) earthquake sequence. Detailed analysis of regional and local waveform data from the 6 June 2003 Bardwell, Kentucky, earthquake indicates that the mainshock has the seismic moment of M0 1.3 (± 0.5) x 1015 N m (Mw 4.0) and occurred at a depth of about 2 (± 1) km on a near-vertical fault plane. A temporary seismic network recorded 85 aftershocks that delineate an east-trending fault approximately 1 km in length. The hypocenters illuminate a vertical plane between 2.0 and 2.7 km depth. The centroid of the aftershock distribution is at 36.875° N, 89.010° W and a depth of 2.4 km. The aftershock cluster is interpreted as a circular fault area with a radius of 0.44 (± 0.03) km. This source radius yields a static stress drop, Δσ = 67 (± 14) bars for the mainshock. The focal mechanism for the mainshock has strike = 90°, dip = 89°, and rake = - 165° with a subhorizontal P axis trending 135°. A formal stress inversion based on the focal mechanisms of the mainshock and ten aftershocks indicates the maximum compressive stress trends 104° with a plunge of 5°. The local stress field near Bardwell is therefore rotated about 40° clockwise relative to 65° for eastern North America as a whole. The Bardwell earthquakes have the opposite sense of slip to earthquakes with east-trending nodal planes that occur near New Madrid, Missouri. This requires a significant local rotation of the stress field over a distance of 60 km. [ABSTRACT FROM AUTHOR]

There has been profound economic and political change in New Zealand in the last decade. It is therefore not surprising that since 1984 there have also been great changes in the urban government of New Zealand. The question posed by this essay is: what do these economic, political and administrative changes mean for urban policy? [ABSTRACT FROM PUBLISHER]